21000527531 has 2 divisors, whose sum is σ = 21000527532. Its totient is φ = 21000527530.

The previous prime is 21000527521. The next prime is 21000527579. The reversal of 21000527531 is 13572500012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21000527531 is a prime.

It is a super-2 number, since 2×21000527531² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21000527531.

It is not a weakly prime, because it can be changed into another prime (21000527521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500263765 + 10500263766.

It is an arithmetic number, because the mean of its divisors is an integer number (10500263766).

Almost surely, 2^21000527531 is an apocalyptic number.

21000527531 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000527531 is an equidigital number, since it uses as much as digits as its factorization.

21000527531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2100, while the sum is 26.

The spelling of 21000527531 in words is "twenty-one billion, five hundred twenty-seven thousand, five hundred thirty-one".